In 1870, the Imperial authorities in London ordered a heraldic designer to come up with a flag and crest for a part of the British Empire called Turks and Caicos. The designer had never heard of the place, but he was sent a sketch by a local artist which showed a typical scene: men wielding long-handled instruments and, behind them, large white mounds. Public interest in Arctic exploration was high, and the designer gave the white mounds a prominent place in the finished crest, a panorama of igloos with doors which remained the emblem of Turks and Caicos until 1968. The people of the islands, which are in the Caribbean, were too shy or too polite ever to tell their Imperial masters that frost and snow were unknown to them, and that the white mounds were heaps of the only product that made money in Turks and Caicos: salt.

By the time the Turks and Caicos got their mad flag, most Victorians in the home country thought of salt, if they thought of it at all, as something cheap and easy to get hold of, as we do now, and had as little interest in where it came from. It wasn’t always like this. When the Romans arrived in Britain, they reported that the locals were so desperate for salt that they would pour sea water on hot charcoal and scrape off the crystals that were left on the charred wood. Now, the US alone produces forty million tonnes of salt a year. Only 8 per cent is for food. More than half is chucked on the roads in winter.

A very long time ago, salt was thought of as a wonderful substance that could fend off starvation by preserving food. At a household level, it was a central element of ritual, myth and hospitality. Yet, as the only commodity that was both precious and necessary, it was for thousands of years a talisman of all that is worst in human behaviour – enslavement, greed, war, the exploitation of the weak by the powerful, the reckless spending of our inheritance from nature.

The Imperial servant’s ignorance about what was going on in the Empire’s salt colony wasn’t entirely innocent. Turks and Caicos is still a British colony, but one of the islands, Salt Cay, is a post-salt desert dotted with iguanas, a monument to three hundred years of ruthless use that ended a few decades ago. The island’s trees were cut down for the salt works, and the land has dried up. Mark Kurlansky, who went there, describes meeting elderly salt veterans, Belongers, who recall that with wages of a shilling and sixpence a day for hard labour shifting salt sacks, and with no alternative employment, they might as well have been slaves.

It’s hard to say who rulers and capitalists have treated worse down the years: the people who have produced the salt, or the people who’ve been obliged to buy it. Even as Turks and Caicos was getting its flag, in another part of the Imperial forest, in India, the British were perfecting a network of regulations and enforcers designed to give British-manufactured salt a competitive edge over locally produced salt by entirely foul means.

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